An image processing apparatus includes an image receiving unit, a phase information extracting unit, a frequency conversion unit, a feature amount extracting unit, and a combining unit. The image receiving unit receives image including biometric information. The phase information extracting unit extracts, from the image information, a first phase component image representing a phase component included in the image information. The frequency conversion unit converts the image information into first frequency information, and converts the first phase component image into second frequency information. The feature amount extracting unit extracts a first feature vector and a second feature vector respectively on the basis of amplitude information of the first frequency information and the second frequency information determined in advance. The combining unit combines the first feature vector and the second feature vector on the basis of a prescribed rule.
